[cc] Show GPU memory usage and overage below FPS counter

cc/tile_manager.h

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_TILE_MANAGER_H_
 #define CC_TILE_MANAGER_H_
 
 #include <list>
 #include <queue>
 #include <vector>
 
 #include "base/hash_tables.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/values.h"
+#include "cc/memory_history.h"
 #include "cc/rendering_stats.h"
 #include "cc/resource_pool.h"
 #include "cc/tile_priority.h"
 
 namespace cc {
 class RasterWorkerPool;
 class ResourceProvider;
 class Tile;
 class TileVersion;
 
@@ skipping 79 matching lines @@
   void ManageTiles();
   void CheckForCompletedTileUploads();
 
   scoped_ptr<base::Value> AsValue() const;
   void GetMemoryStats(size_t* memoryRequiredBytes,
                       size_t* memoryNiceToHaveBytes,
                       size_t* memoryUsedBytes) const;
   void GetRenderingStats(RenderingStats* stats);
   bool HasPendingWorkScheduled(WhichTree tree) const;
 
+  const MemoryHistory::Entry& memory_stats_from_last_assign() const { return memory_stats_from_last_assign_; }
+
  protected:
   // Methods called by Tile
   friend class Tile;
   void RegisterTile(Tile* tile);
   void UnregisterTile(Tile* tile);
   void WillModifyTilePriority(
       Tile* tile, WhichTree tree, const TilePriority& new_priority);
 
  private:
   void SortTiles();
@@ skipping 45 matching lines @@
   // when all the image decoding tasks finish.
   TileList tiles_with_image_decoding_tasks_;
 
   typedef base::hash_map<uint32_t, skia::LazyPixelRef*> PixelRefMap;
   PixelRefMap pending_decode_tasks_;
 
   typedef std::queue<scoped_refptr<Tile> > TileQueue;
   TileQueue tiles_with_pending_set_pixels_;
   size_t bytes_pending_set_pixels_;
   bool ever_exceeded_memory_budget_;
+  MemoryHistory::Entry memory_stats_from_last_assign_;
 
   RenderingStats rendering_stats_;
 
   int raster_state_count_[NUM_STATES][NUM_TREES][NUM_BINS];
 
   DISALLOW_COPY_AND_ASSIGN(TileManager);
 };
 
 }  // namespace cc
 
 #endif  // CC_TILE_MANAGER_H_